The long term failure rate of total joint replacement makes it an unsuitable selection for the treatment of arthritis in the young and middle aged patient. A more appropriate treatment for these patients is a procedure that restores the joint surfaces back to their normal state with biologically competent tissues. It has been demonstrated that rib perichondrium transplanted into a joint will proliferate to form a hyaline cartilage, and that this neocartilage continues to mature until it is almost identical to the tissue it is replacing. The objectives of this proposal are to develop and test a system of graft fixation wherein the perichondrium is secured to a bone plug utilizing a dacron mesh laid over the perichondrium. The composite dacron perichondrium/bone plug will be placed into the medial femoral condyle of the rabbit. The knee will be treated for 2 wks. with intermittent continuous passive motion. The regenerated neocartilage will be studied both short term (6-12 wks.) and long term (26, 52, 78 and 104 wks.) and will be evaluated using morphological, biochemical and biomechanical techniques. Normal articular cartilage will serve as a control. The goal is to achieve a clinical biologically acceptable result from perichondrial transplantation.